The collection of fibers (also known as sliver) to be drawn and combed in a combing and drawing frame of this kind is relatively wide. For example, the working width of a combing and drawing frame may be 160 mm and the width of the collection of fibers to be processed therein may be as wide as the working width of the combing and drawing frame. The fibers in the collection of fibers, or sliver, may be cotton or other fibers such as rayon staple fibers, man-made fibers or the like which are similar in length to cotton fibers.
In a known combing and drawing frame (see German patent document No. 28 03 467 and U.S. Pat. No. 4,083,085) the two rolls of the pair of feed rolls are mounted at a small spacing from the comber cylinder and supply the sliver directly to the comber cylinder and comber bed.
However, owing to the high loading pressure required for clamping the sliver in the nip of the pair of feed rolls, the lower feed roll must have a large external diameter so that it is capable of absorbing the high loading pressure. As a result, the nip of the pair of feed rollers is at a relatively large spacing from the point where the comber cylinder starts to comb the sliver, and this leads to substantial irregularities in the sliver.